Constructing ZnTe Spherical Quantum Well for Efficient Light Emission

Summary, in English

ZnTe colloidal semiconductor nanocrystals (NCs) have shown promise for light-emitting diodes (LEDs) and displays, because they are free from toxic heavy metals (Cd). However, so far, their low photoluminescence (PL) efficiency (∼30%) has hindered their applications. Herein, we devised a novel structure of ZnTe NCs with the configuration of ZnSe (core)/ZnTe (spherical quantum well, SQW)/ZnSe (shell). The inner layer ZnTe was grown at the surface of ZnSe core with avoiding using highly active and high-risk Zn sources. Due to the formation of coherently strained heterostructure which reduced the lattice mismatch, and the thermodynamic growth of ZnTe, the surface or interface defects were suppressed. A high PL efficiency of >60% was obtained for the green light-emitting ZnSe/ZnTe/ZnSe SQWs after ZnS outer layer passivation, which is the highest value for colloidal ZnTe-based NCs. This work paves the way for the development of novel semiconductor NCs for luminescent and display applications.

• Author: Kequan Cao; Binbin Yu; Fei Huang; Qinying Pan; Junfeng Wang; Jiajia Ning; Kaibo Zheng; Tõnu Pullerits; Jianjun Tian
• Department/s: LTH Profile Area: Nanoscience and Semiconductor Technology; LU Profile Area: Light and Materials; Chemical Physics; NanoLund: Centre for Nanoscience; LTH Profile Area: Photon Science and Technology
• Publishing year: 2024
• Language: English
• Pages: 5238-5245
• Publication/Series: Nano Letters
• Volume: 24
• Issue: 17
• Links: http://dx.doi.org/10.1021/acs.nanolett.4c00734
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Condensed Matter Physics (including Material Physics, Nano Physics); Physical Chemistry (including Surface- and Colloid Chemistry)
• Keywords: coherently strained heterostructure; high quantum yield; mismatch defects; Spherical quantum well; thermodynamic shell growth
• Status: Published
• ISBN/ISSN/Other: ISSN: 1530-6984